The first stage of the human embryonic stem(ES) cell research debate revolved aroundfundamental questions, such as whether theresearch should be done at all, what types ofresearch may be done, who should do theresearch, and how the research should befunded. Now that some of these questions arebeing answered, we are beginning to see thenext stage of the debate: the battle forproperty rights relating to human ES cells. The reason why property rights will be a keyissue in this debate is simple and easy tounderstand: it costs a great deal of money todo this research, to develop new products, andto implement therapies; and private companies,researchers, and health professionals requirereturns on investments and reimbursements forgoods and services. This paper considersarguments for and against property rightsrelating to ES cells defends the followingpoints: (1) It should be legal to buy and sellES cells and products. (2) It should be legalto patent ES cells, products, and relatedtechnologies. (3) It should not be legal tobuy, sell, or patent human embryos. (4) Patentson ES cells, products, and related technologiesshould not be excessively broad. (5) Patents onES cells, products, and related technologiesshould be granted only when applicants statedefinite, plausible uses for their inventions. (6) There should be a research exemption in EScell patenting to allow academic scientists toconduct research in regenerative medicine. (7)It may be appropriate to take steps to preventcompanies from using patents in ES cells,products, and related technologies only toblock competitors. (8) As the field ofregenerative medicine continues to develop,societies should revisit issues relating toproperty rights on a continuing basis in orderto develop policies and develop regulations tomaximize the social, medical, economic, andscientific benefits of ES cell research andproduct development